[BEAM-2404] BigQueryIO reading stalls if no data is returned by query

• Type: Bug
• Status: Open
• Priority: P3
• Resolution: Unresolved
• Affects Version/s: 2.0.0
• Fix Version/s: Not applicable
• Component/s: io-java-gcp
• Assignee: Unassigned
• Reporter: Andre
• Created: 02/Jun/17 08:39
• Updated: 03/Jun/22 17:20

Description

When running a BigQueryIO query that doesn't return any rows (e.g. nothing has changed in a delta job) the job seems to stall and nothing happens as no temp files are being written which I think might be what it is waiting for. Just adding one row to the source table will make the job run through successfully.

Code:

PCollection <TableRow> rows = p.apply("ReadFromBQ",
 BigQueryIO.read()
 .fromQuery("SELECT * FROM `myproject.dataset.table`")
 .withoutResultFlattening().usingStandardSql());

Log:

		
Jun 02, 2017 9:00:36 AM org.apache.beam.sdk.io.gcp.bigquery.BigQueryServicesImpl$JobServiceImpl startJob
INFO: Started BigQuery job: {jobId=beam_job_batch-query, projectId=my-project}.
bq show -j --format=prettyjson --project_id=my-project beam_job_batch-query
Jun 02, 2017 9:03:11 AM org.apache.beam.sdk.io.gcp.bigquery.BigQuerySourceBase executeExtract
INFO: Starting BigQuery extract job: beam_job_batch-extract
Jun 02, 2017 9:03:12 AM org.apache.beam.sdk.io.gcp.bigquery.BigQueryServicesImpl$JobServiceImpl startJob
INFO: Started BigQuery job: {jobId=beam_job_batch-extract, projectId=my-project}.
bq show -j --format=prettyjson --project_id=my-project beam_job_batch-extract
Jun 02, 2017 9:04:06 AM org.apache.beam.sdk.io.gcp.bigquery.BigQuerySourceBase executeExtract
INFO: BigQuery extract job completed: beam_job_batch-extract
Jun 02, 2017 9:04:08 AM org.apache.beam.sdk.io.FileBasedSource expandFilePattern
INFO: Matched 1 files for pattern gs://my-bucket/tmp/BigQueryExtractTemp/ff594d003c6440a1ad84b9e02858b5c6/000000000000.avro
Jun 02, 2017 9:04:09 AM org.apache.beam.sdk.io.FileBasedSource getEstimatedSizeBytes
INFO: Filepattern gs://my-bucket/tmp/BigQueryExtractTemp/ff594d003c6440a1ad84b9e02858b5c6/000000000000.avro matched 1 files with total size 9750